Railway traffic controlling apparatus



March 8, 1932. J. E. M CAULLEY I RAILWAY TRAFFIC CONTROLLING APPARATUS Filed April 1, 1931 2 Sheets-Sheet l INVENTOR. \7: E. Ma Gaul/11y A ATTORNEY March 8, 1932. J. E. M CAULLEY RAILWAY TRAFFIC CONTROLLING APPARATUS INVENTOR IEMaKZaul/c v A TTORNE Y.

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Patented Mar. 8, 1932 UNITED STATES PATENT OFFICE JOHN E. MCCAIJ'LLEY, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO THE UNION SW'I'ICH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA RAILWAY TRAFFIC CONTROLLING APPARATUS Application filed April 1, 1931. Serial No. 526,826.

My invention relates to railway traffic controlling apparatus, and particularly to signaling apparatus for stretches of single track over which trailic moves in both directions be- 7 tween passing sidings.

I will dscribe one form of railway trailic controlling apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1

, and 1", when placed end to end with Fig. 1

on the left, constitute a diagrammatic view illustrating one form of railway trai'iic controlling apparatus embodying my invention.

form apluralityof track sections 1, 2,

6, 7 and 8. of a switch E with a'passing siding F and Referring to the drawings, the reference character A designates a stretch of railway track between'points C and D, which track is divided by means of insulated 3011113S a to 3, 41, 5, Section 1 is connected by means section 8 is likewise connected by means of a switch E with a passing siding F The control means for the switches E and E form no part of my invention, and is therefore not shown in the drawings.

Each track section is provided with the usual track circuit comprising a suitable source of current, here shown as a track battery 9, connected across the rails at one end of the section, and a track relay designated by the reference character T with a distinguishing exponent, connected across the rails at the opposite end of the section.

Eastbound traffic over stretch C-D, that is, trafiic moving from left to right, is governed by trackway signals H H*, H and H located at the left hand end of sections 1, 1, 6 and 8, respectively, and westbound traffic is governed by'signals J J, J and J located at the right hand end of sections 8, 5, 3 and 1,

respectively. A signal H a is also located at the right hand end of siding F forgoverning the entrance of eastbound trafiic into stretch -1) from the siding F and asimila-r signal J m is located at the right handend of siding F for governing the entrance of westbound traific into stretch 0-1) from the siding F These signals may be of any suitable fornn'and are here shown as light signals each comprising three lamps G, Y and R arranged when energized to indicate proceed, caution, and stop, respectively. For convenience, in describing my invention, 1 shall hereinafter refer to signals H H a, J and J a, as head block signals; the signals H211 J and J as intermediate signals, and thesignals H and J as leaving signals, but it is to be understood that these particular designations have no especial significance, and that there are no essential difierences between the signals thus designated, other than the differences in their locations.

The head block signals H and H a are controlled by two slow acting relays SH and SE 0; respectively, and by a line relay SH. As here shown, the line relay SH is of the polarized type, so that it is responsive to reversals in the polarity of the current supplied thereto; and this relay is so designed that when its polar armature is moved to one position, it will remain in such one position until the relay is supplied with current of the opposite polarity from that which caused the polar armature to move to such one position; Referring particularly to signal H when relay SE is deenergized, a circuit is completed for lamp R of this signal, and current flows from terminal B of a suitable source of current not shown in the drawings through back contact 1010" of relay SR wire 11, and the filament of lamp R to terminal X. Under these conditions lamp R of signal H is illuminated, and the signal displays a stop indication. lVhen relay SH is energized, and the polar contacts of relay SH are swung to their left-hand or normal positions, in which positions they are illustrated in the drawings, a circuit is completed for lamp G of signal H and current flows from terminal B through front contact 10-10 of relay SH wire 12, normal contact 13-13 of relay SH, wire 15, and the filament of lamp G to terminal X. Under these conditions, lamp G is lighted, and signalH displays a proceed indication. When relay SE is energized, and the polar contacts of relay SH are swung to their right hand or reverse positions, a circuit is completed for lamp Y of signal H and current flows from cation, but

signal H? displays a caution or a proceed in terminal through from contact 10-10 of relay SI-P, wire 12, reverse contact 13-l3 of relay SH, wire 14, and the filament of dication, according as the reverse ornorinal contacts of the line relay SH are closed. The circults for signal H 02 are similar to those ust traced for signal H and will be understood from an inspection of the drawings without describing them in detail.

The head block signalsel and I a are controlled, by. two slow acting relays SJ and Sella and by polarized line relay SJ in thesame manner as the signals H and El a are controlled by the two slow acting relays SH SH a and bythe polarized line relay SH. The control circuits for the signals J and J a are omitted from the drawingsto simplify the disclosure.

' "Each of the signals H H H J J and J is'co'ntrolled bya line relay designated by Till lighted and signal H displays a the reference character S with a suffix which is thesame as the'reference character for the associated'signal. Each of these relays is a polarized relay similar to the line relay SH previously described. Referring particularly to signal H when relay SH is deenergized, a circuit iscompleted for lamp R of this signal, and'currentflows from terminal B through'bacl: contact 28---28 of relay SE1 wire 29, and the filament of lamp R to terminal X. Under these conditions, lamp R is stop indication. When relay SE is energized in the reverse direction 'so that its front contacts lamp G of signal-H V therefore,that signal H are closed and its polar contact 81 is swung to its right-handor reverse position, a circuit is completed for-lamp Y of signal H and current fiows from terminal B through front contact 218-28 of relay SE wire 30, reverse contactiill-l of relay SE1 wire 82, and the filament of lamp Y to terminal Under these conditions lamp Y is lighted, and'sig-o nal H displays a caution indication. When relay SH is energized in its normal direction so' that its polar contact 31 1s swung to its left-hand or normal position, as illustrated in the'dra'vvings, a circuit is completed for g and current flows from terminalBthrough front contact 28-28 of I relay SE wire 30,'norinal contact Ed-31 of relay SE wire 33, and the filamentof lamp G to-terminal X. ,Underthese conditions, lamp Gishghted, and signall-l d splays a proceed indicationt It Will'be apparent,

t on, or proceed indicationaccording as line relay SH isj deenergized, or, is, energized 1n its reverse orits normal direction. The con-1 SH. The circuit controller K displays a stop, cau-.

trol circuits for each of the signals H, H J J and J are similar to those just traced for signal H and they have therefore been omitted from the drawings in order to simplify the disclosure.

The relays SH and SI-Pa are controlled by a circuit controller K the track relay T a circuit controller L and the line relay is oper'atively connected with'the switch E and, in the form here shown, comprises a contact 1616 which is closed when and only when the switch o ccupies its full normal position, n which position it is shown 1n the drawings,

and a contact 1616 which is closed when and only when the switch occupies its full reverse position. The circuit controller L as here shown, is manually operable; and comprises two contacts 1718 and 1920, one of which is closedwhen the circuit controller occupies one position, and the other of which is closed when the circuit controller occupies another position. In actual practice, the circuit controller L will usually be replaced by the contacts of a relay which is controlled from a remote point, as by alever of an interlocking machine, or by code sent out from a dispatchers oflice.

v Relay SE is provided with a circuit which passes from terminal B through front contact21 ofrelay. SH, wire 22, contact 19-20 of circuit controller 'L wire '23, front contact 2a of track relay T wire 25, contact 16-16 of circuit controller K wire 26, and the winding of relay SH -to terminal X. henthis circuit is closechline relay SH becomes energized, thereby causing signal H to indicate caution or proceed according as line relay SH is thenenergized in its reverse or its normal direction, as pointed out hereinbeforeI It will be noted, however, thatthis circuit cannot be closed unless track section 1 is unoccupied and switch E occupies its normal position, in which'position it is illustrated in the drawings.

Relay S11 0: is provided with a circuit which is similar to the circuitijust traced for relay SH, and which passes from terminal B through frontcontact 21 of relay SH, wire 22, contact 1920of circuitcontroller L wire 23, front contact 24- of track relay T wire 25, contact 1616 of circuit controller K wire 27, and thewinding of relay Sl-l a to terminal X. when this circuit is closed, relay SH a becomes energized,

thereby causing signal H a to indicate cau tionor proceed according as line relay SH is energ zed 111 its reverse or normal direction. It will-be noted, however, that thisxcircuit cannot be closed unless track section lis unoccupled, and switch E occupies fits reverse The circuit controllerK is similar to the circuit controller K and is operated by the switch E in the same manner as the circuit controller K is operated by the switch E The circuit controller L is likewise similar to the circuit controller L The circuits for the relays SJ and SJ -a are similar to the circuits for the relays SH and SH a, re spectively, and will, beunderstood from an inspection of the drawings without describing them in detail.

Each of the line relays with the exception f line relays SH and SJcontrols a slow re leasing repeater relay designated by the reference character R with a prefix which is the same as the reference character for the associated line relay. Each repeater relay is supplied with current from the terminals B and X over a front contact of the associated line relay, and it will be apparent therefore that each repeater relay is energized or deenergized according as the associated line relay is energized or deenergized. Associatedwith each of the intermediate signals H H J and J is directional stick relay designated. by the reference charact-er M with the same exponent as the eX-. ponent for the reference character of the associated signal. Each repeater relay is controlled by the track relay for the section of track immediately in advance of the associated signal in the direction of traffic'governed by the signal and by the repeater 'relay for the line relay which controls the associated 5 signal. Referring particularly to the relay M for example, when track relay T is deenergized and repeater relay SEER- is energized, a pick-up circuit is completed for this relay which passes from terminal B through back contact of track relay T wires 36 and 37, front contact 3 838 of repeater relay SE 3, wires 39 and 40, and the winding of relay M to terminal X. lVhen this circuit is closed, stick relay M becomes energized and completes a stick circuit which passes from terminal B, through back contact 35 of track relay T wires 36 and 44, front contact 42 of relay M wires 43 and 40, and the winding of relay M to terminal'X. Relay M is further provided with another stick circuit which passes from terminal B through back contact 88-88" of repeater 'relay SI-FR, wires 87 and 41, front contact42 of relay M wires 43 and 40, and the winding of relay M to terminal it will be noted that this latter stick circuit for stick relay M is closed if and only if repeater relay SH R is deenergized when'stick relay M is energized. The

circuits for eachof the remaining stick reare similar to those just tracedfor the tick relay Mt, and .will beapparent from an ;i::is )'e ction. of the drawings without'describing tl'iem in detail.

The line-relay SJ is controlled by a front contact 44 of track relay T and by manually operable means forming no part of my invention and therefore not shown in the drawings. For purposes of the present disclosure, it is sufficient to say that this relay will be deenergized whenever track section 1 is occupied, and that when this section is unoccupied this relay may be deenergized, or energized in either its normal or reverse direction by the manipulation of a manually operable device or other suitable control means located at a remote point.

The line relay SE is controlled by a front contact 44 of track relay T and by manually operable means located at a remote point in the same manner as the relay SJ is controlled by a front contact 44 of track relay T and by manually operable means.

Line relay SJ is provided with a circuit which is controlled in part by repeater relay SJ R and which passes from terminal B through back contact 4545" of repeater relay SJ 3, line wire 46, winding of line relay 8J wire 47, back contact 48 of stick relay M wire 49, frontcontact 50 of track relay T line wire 51, front contact 52 of track relay T front contact 53 oft-rack relay T contact 1718 of circuit controller L wire 54, back contact 55 of relay Slim, wire 56, back contact 57 of relay SE wire 59, and back contact 5858 of repeater relay $3 K to terminal C. lVhen this circuit is closed, line relay SJ is supplied with current of what I shall term reverse polarity, and under these conditions, the polar contact of this relay is swung to its right hand or reverse position so that signal J displays a caution indication as shown in the drawings. Relay SP is also provided with a circuit which is similar to to the circuit just traced for this relay, except that this circuit includes front contacts 45-45 and 5858 of relay SJ R instead of back contacts 4545" and 5858 of relay SJ R. Vhen this latter circuit is closed, it will be obvious that the polarity of the current supplied to relay SJ? is reversed, and under these conditions, the polar contact of this relay is swung to its left hand or normal position, so that signal J displays a proceed indication.

Line relay SH is provided with a circuit which passes .LTOH] terminal B through front contact 6060 of repeater relay SH R, line wire 61, winding of relay SH, wire 62, back contact 63 of stick relay M wire 64, front contact 65 of track relay T line wire 66, front contact 67 of track relay T front contact 68 of track relay T contact l718 of circuit controller L wire 69, back contact 70, of relay SJ a, wire 71, back contact 72 of relay SJ wire 73, and front contact 7474 of repeater relay SH R to terminal C. When this circuit is closed, relay SH is supplied with current of reverse polarity, and its polar contact is swung to its right hand or reverse position so that signal H displays a Ila":

caution indication. Relay SH is alsoprovided' with another circuit which is similar to the circuit just traced except that this circuit includes back contacts 6060 and7474 of relay SH R instead of front contacts 6O60 and 7474 of this relay. Itwill be apparent that when this latter circuit is closed, relay SH is supplied with current of normal'polarity and, under these conditions,

the polar contact of relay SH is swung to its left hand or normal position so that signal H displays a proceed indication. V

Line relay SH is provided with a circuit which is controlled in part by-repeater relay SHR, and which passes from terminal B through front contact 7 5-7 5 of repeater relay SHtR, wire 77, back contact 78 of repeater relay SJ R, wire17 9, front contact'80 of track 1 circuit which passes from terminal B through back contact 75.- of line relay SH R, line wire 85, winding of relay SH, wire 84, front contact 83 of track relay T front contact 82 of track relay T line wire 81, front contact of track relay T wire 79, back contact 78 of repeater relay SJ R, wires 77 and 87, front. contact 88 of stick relay M, wire 89, and back contact 8686 of repeater relay SH R to terminal C. WVhen thislatter circuit for relay SH is closed, relay SH is supplied with current ofreverse polarity and its polar contacts are swung to their right hand or reverse posltions.

Line relay SH is provided with a circuit 7 which is controlled in part by repeater relay SH R, and which passes from terminal B i 7 through front contact 9090 of repeater relay SH R, wires 91 and 92, back contact 93 of repeater relay SJ R, wire 94, front contact 95 of track relay T line wire 96, front contact 97 of track relay T, wire 98, back contact'99- of stick relay M Wire 100', winding of relay SH, line wire 101, and front contact102'102" of repeater relay SH Rback to: terminal C. lVhen this'circuit is-closed line V relay SH is supplied withcurrent of normal 7 v polarity and its'polar contacts are swung to 1 th ir} left hand or normal positions, in which t-hey are illustrated inthe drawings, so that signal H then'displays a proceed indication. Relay SH is also provided with another circuit which passes from terminal B'through back con-tact 90 90 of; repeater relay SH R, line wire 101, winding of relay SH, wire 100,

, back contact '99 of stick relay Miwirei 98,

front contact 97 of track relay T line wire 96, front contact 95 of track relay'l wire 94,- back contact 93 of repeater relay SJ R, wires 92 and 103, front contact 104 of stick relay M wire 105 and back contact 102'102- of repeater relay SH R to terminal C. When this circuit is closed, line relay SH is'supplied with current of reverse polarity, and its polar contacts are swung to their right hand or reverse positions so that signal H displays acaution indication. A

1 Line relay SJ is provided with a circuit which is controlledin part by repeater relay SJ R- and which passes from terminal B through front contact 106106 of'repeater relay SJ R, wire 107, back contact 109 of repeater relay SH R, wire 110, front contact 111 of track relay I, line wire 112, front contact 113 of track relay T wire 114, back contact 115 of stick relay M Wire 1163, winding of relay SJ line wire 117, and front contact 118118 of repeater relay SJ R to terminal C. WVhen this circuit is closed, relaySJ is supplied with current of normal polarity,

and its polar contacts are swung to their left-hand or normalpositions, so that signal J displays a proceed indication. Linerelay S5 is further provided with a circuit which passes from'terminal B through back contact'1'06106 of repeater relay SJ R, line wire 117, winding of line relay SJ wire 116, back contact 115 of stickrelay M wire 114, front contact 113 of track relay T line wire 112, front contact 111 of track relay T wire 110, back contact 1090f repeater relay SHR, wires 107 and119, front contact 120 of stick relay M wire 121, and had: contact 118118 of repeater relay SJ R to terminal C. 'VVhen this latter circuit is closed, relay SJ is supplied with current of reverse polarity, and its polar contacts are swung to their right-hand or reverse positions, so that signal J displays a caution indication.

Line relay SJ is provided with a circuit which is controlled in part by repeater relay SJ R- and which passes from terminal B through front contact 122122 of repeater relay SJ R, wire 124, back contact 125 of repeater relay SH R, Wire 126, front contact 127 of track relay T, line wire 128, front con act 129 of track relay T front contact 130 of track relay T wire 131, winding of relay SJ, line wire 132, and front contact 133133 of repeater relay SJ R to terminal C. WVhen this circuit is closed, line relay SJ is sup-plied with current of normal polarity and its polar contacts are swung'to their left-hand or normal positions. Line relay I SJ is also provided with a circuit which passes from terminal B, through backcon tact 122-122 of repeater relay SJ R, line wire- 132 winding of relay SJ, wire 131, front contact130 of track relay T front contact 129 oftrack relay T line wire 128, front contact 127 of trackrelay T wire 126,

back contact of repeater relay SH R,

wires 124: and 133, front contact 134 of stick relay M wire 135, and back contact 133-133 of repeater'relay SJ E to terminal C. When this circuit is closed, line relay SJ is supplied with current of reverse polarity, so that its polar contacts are swung to their right-hand or reverse positions.

As shown in the drawings, stretch (1-1) is unoccupied so that all of the track relays T are energized. Each of the stick relays H is deenergized. Switch E occupies its normal position, and contact 16-16 of circuit con troller K is therefore closed and contact 16-16 is opened. Line relay SH is deenergized. Repeater relay SH R is therefore'likewise deenergized, and signal H displays a stop indication. Circuit controller L occupies the position in which contact 17-18 is open, and contact 19-20 is closed. Both circuits previously traced for line relay SH are therefore open at contact 17-18 of circuit controller L and relay SH is therefore deenergized. Signal H accordingly displays a stop indication, and repeater relay SH R is deenergized. Since repeater relay SH R and stick relay M are both doenergized, both circuits previously traced for line relay SE are open, and this relay is thereforedeenergized. Signal H therefore displays a stop indication, and repeater relay SE 3 is deenergized. The one circuit previously traced for line relay SH is interrupted at front contacts 75-75 and 86-86 of repeater relay SH R, and the other circuit for i this relay is interrupted at front contact 88 of stick relay M Line relay SH is therefore deenergized. Line relay SJ is also deenergized. Signal J therefore displays a stop indication and repeater relaySJ R is deenergized. Switch E occupies its normal position and contact Iii-16 of circuit controller K is therefore closed while contact 16-10 is open. Circuit controller L occupies the position in which its contact 17-18 is closed and its contact 19-20 is opened. The circuit previously traced for each ofthe relays SE and Sl-Pa is open at front contact 21 of line relay SH, and these relays energized, so that signals H and HM both display a stop indication, The circuit previously traced for line relay SJ including back contacts 58-58 and 15-5 of 'repeater relay SJR is closed, and line relay SJ is therefore energized in its reverse di rection, so that signal J displays a caution indication. The circuit previously traced for line relay SJ 5 including front contacts 106-106 and 118-1181of relay' 853R- and back cont-act 109 of'repeater relay SH lt is also closed, so that relay SJ is energized in its normal direction. Signal J therefore dis-' plays a proceed indication. I Line relay-SJ is supplied with currentof normal'polarity over the circuit previously traced including front contacts 122-122 and 133-133 of repeater are therefore derelay SJ R and back contact 125 of repeater relay SH R, and relay SJ is therefore also energized in its normal direction. 1 Since relay SJ is energized and since contact 19-20 of circuit controller L and contact 16-16 of circuit controller K are both closed, relay SJ is energized. Signal J therefore displays a proceed indication. Signal J a, however, displaysa stop indication, the circuit for relay. SJ a being open at front contact 16-16 of circuit controller K Tn explaining the operation of the apparatus a whole, I will first assume that with the parts in the positions just described, the train despatcher wishes to clear the signals governing eastbound traffic through the stretch (1-1) to permit a train approaching from the left on the main track A to enter the stretch. To do this he first operates circuit controller L to open contact 19-20 of this circuit controller and to close contact 17-18. The opening of contact 19-20 deenergizes relay SJ which causes signal J 8 to display a stop indication, thereby preventing a westbound train from entering stretch (3-1).

The operator next energizes line relay SH nal H to display a proceed indication. The

energization of line relay SH also causes re-- peater relay SH R- to pick up, and this, in turn,completes the circuit previously traced for line relay SH including contact 17-18 of circuit controller L and front contacts 60-60 and T l-7% of repeater relay SH R, so that line relay SH becomes energized in its normal direction. The energization of reley SH, in turn, causes signal H to display a proceed indication, and also causes repeater relay SH R to become energized. The train despatcher next operates circuit controller L to open contact 17-18, and close the contact 19-20, of this ing of contact 17-18 interrupts the circuit which was previously closed for line relay SJ 3 at this contact, and becomes deenergized. This causes signal J 3 to display a stop indication, and also deenergizes repeater relay SJ 3. The opening of front contacts 106-106 and 118-118 of repeater relay SJ 3 interrupts the circuit previously traced for line relay SJ", and this relay also becomes deenergized. As a result, signal J then displays a stop indication, and repeater relay SJ R becomes deenergized. The opening of front contacts 122-122 and 133-133 of repeater relay SJ R interrupts the circuit for line relay SJ and this relay likewise becomes deenergized. The closing of back contact 93 of repeater relay SJ R cornpletes the circuit previously traced for line relay Sit-I including front contact-s 90-90 and 102-102 of repeater relay SH R, and relay SH is therefore supplied with current of normal polarity, so that this relay becomes energized in its normal direction. Theencircuit controller. The open-" relay SJ 3 therefore ergization of relay 'SHtin its normal direc- V energized and opens its front contacts.

. line relay SH? therefore tion causes. signal H to display a proceed indication and also-causes repeater relay SI-PR to become energized. When front contacts 'Z'5 .75 and-86i-8c6 of repeater relay SI'PR becomeclosed, they complete the circuit previously traced for line relay SH and line relay SH therefore normal direction. The closing of front contact 21 of relay SH completes the circuit for relay SH and this relay thereforepicks up and closes. its frontcontact lO .lO This, inturn, completes the circuit for the lamp G ofsignal H and signal H therefore displays a proceed indication. V

I will. next assume that with signals J J a, J J and J at stop, and signals H H, H and H at proceed, an eastbound train traverses the stretch GD- When the train enters section 1, track relay T becomes de- The opening of front contact 24 of track relay T "interruptslthe circuit which was previously SH at this contact, and become deenergized,

so that signal H then displays a stopindicaclosed for line relay tion. Theopening'of front contact 44 of track relay T? interrupts the I thus preventing the train despatcher from energizing this relay to "cause signal J to indicate caution or proceed as long as the train 7 occupies section 1. The. opening of front conremains open andsignal H tacta83 of track relay T lay SH; When the train enters section 2,

T track relay T becomes deenergized and opens its front contacts.

The opening of front contact 82 vof'this relay interrupts both circuits previously traced for line relay SH, and the opening of front contact 52 interrupts will remain deenergized aslong as'the train occupies section 2. When the train leaves section 1, track relay T again becomes energized, but, since line relay at front contact 82 of track relay T due to the train insecti on 2, the circuit for relay SH therefore continues to indicate stop. When the train enters The opening of front contact of track re lay T maintains relay SH in its-deenergized condition even though track picks up due to the pletely out of section 2. Similarly, the opening of front contact 50 of track relay T prevents the circuit for relay SJ 3 from becoming I closed as long as the train occupies section zation of line relay SJ ouslytraced for line becomes energizedv in its circuit for relay SJ deenergizes line re- 0th circuitspreviously traced for line relay SJ t, thus insuring that both of these relays SH is then deenergiz'ed" relay T now tra1n having passed comclosing of. back because this pick-up and stick relay M therefore remains deenergized; Whenv the train, enters section 4, track relay T becomes deenergized. The openingof front contact 97 of this relayinterrupts both circuits previrelay SH and this latter relay therefore becomes deenergized. This causes signal H to display a stop indication, and also causes repeater relay SE 1 to be come deenergized. Due to the slow releasing characteristics of relay SH R, however, a brief interval of time elapses after relay SH becomes deenergized and before front contact 38-38 of repeater relay SI-PR opens,and since back contact 35 oftrack relay T is then closed, the pick-upcircuit for stick-relay M becomes completed during this interval, so that stick relay M now becomes energized. As soon as stick relay M closes'its frontcontact 42, the stick circuit previously'traced for this relay including'back contact 35 of track relay T becomes'closed, and when back con- 7 tact 8838 of repeater relay SHR becomes closed, the other stick circuit for this relay becomes closed- It willbe apparent, therefore, that when stick relay M has once" become energized, this relay will remain energized as long as track relayT or repeater, re laySH Ft is deenergized. 'One function of the stick circuit for relay M including back contact 35 of trackrelay T lS to, insurethat relay M will not drop during'the interval of traced for line relay SH including'this contact is completed, and line-relay SH therefore becomes 'energizedlin its reverse direction, This. completes the circuit forrelaySH and relay SH therefore picks up. 7 Since relay SH is then energized in its reverse direction, this causes signal H to display a caution indication. The opening of front contact 48 of stick relay M again interrupts the circuit for line relay SJ so that signal J will continue to indicate stop even though the train new passes out of section 3 and permits track relay T to pick up. When the train enters section 5, and deenergizes track relay T both circuitspr'evt ously traced-for line-relay'SPI areopened at back contact of track relay T and both circuits previously traced for, line relay S-T arelikewise opened" at front'contact 113 of trackrelay T Theserelays therefore remain deenergized as longas the train occupies section 5', and signals H and J therefore both continue to indicate stop, und-erthese conditions. When'the train passes completely out of section'a, track relay T picks up, but, this has no immediate effect on the apparatus. When the train enters section 6 becomes deenergizecl and stick aassed out of section 5 the circuit sreviousl traced for line relay SPF including back contacts 9090 and 102102 of repeater relay SH R becomes closed, and relay SH therefore becomes energized in its reverse direction. This causes signal H to display a caution indication, and also causes repeater relay SI PR to become energized. The energization of repeater relay SH R reverses the polarity of the current supplied to line relay SH, provided that a following train has not entered stretch CD, and this latter relay then becomes energized in its normal direction. This, in turn, causes signal H to display a proceed indication. The energization of repeater relay SH R also interrupts the stick circuit for stick relay M4, thereby restoring stick relay M to its normaldeenergized condition. When the train enters section 7, the subsequent deenergization of track relay T holds the circuit for line relays SE and SJ open, so that these relays cannot becomes energized while the train occupies this section, thus insuring that signals H, J and J a, will continue to display'a stop indication under these conditions. When the train enters section 8, the circuit for line relay SH is'interrupted at front contact 44 of track relay T and this relay therefore'becomes deenergized, so that signal H now displays a stop indication. When the train passes out of section 8, track relay T again becomes energized and closes its front contacts. If the circuit for line relay SE is then open at the control point, so that repeater relay SH R is deenergized, line relay SH will become energized in its reverse direction. This will cause signal H to display a caution indication and also causes repeater relay SH R to become energized. If the circuit for line relay Si 3 is closed at the control point, however, when track relay T3 picks up so that repeater relay sum is then energized, line relay SH will become energized in its reverse direction and signal H will display a proceed indication. The energization of repeater relay SH R reverses the polarity of the current. supplied to line relay SH thus causing this line relay to become energized in its normal direction, andhence,

causing signal H to display a proceed indication. The energization of repeater relay SH R also deen-ergizes stick relay M thereby restoring the apparatus to the condition which it occupied before the eastbound train traversed the stretch C-D.

Then the signals H H H and H have been cleared to permit an eastbound move,

and it is desired to restore the parts to the conditions in which they are illustrated in the drawings, the despatcher will proceed in a manner exactly opposite to that described in connection with the clearing of the signals for an eastbound move. The operation of the apparatus under one from an inspection of the drawings without describing them in detail.

The operation of the apparatus when the parts are in the condition shown and a westbound train traverses the stretch C-D, is similar to that previously described for an eastbound train traversing the stretch. and Will also be understood from an inspection of the drawings without describing it in detail.

If the parts are in the positions shown and the despatcher wishes to permit a train in the siding F to enter the stretch CD, he will of course reverse the switch E". This will open contact l(il6 of circuit controller K and will close contact 16l6 of this circuit controller. Relay S5 will then become deenergized and relay SJ Q will become energized so that signal J will. display a stop indie. tion and signal J a will display aproceed indication. The operation of the apparatus in all other respects will be similar to that when a westbound train enters the stretch C-D from the main track A.

If the despatcher wishes to permit an eastbound train to enter stretch C-D from the siding 1*, he will first reverse switch E and then will proceed in the manner previously described. Under these conditions relay Sl-Pa will become energized and relay SH will remain deenergized so that signal Il a will indicate proceed instead of signal H The operation of the remainder of the appara tus under these conditions is the same as that previously described and will be understood without further description.

It should be pointed out that with apparatus embodying my invention, it is impossible for the despatcher to clear either head block signal until the first opposing head block signal, as well as all the intervening opposing intermediate signals, have been caused to indicate stop. This arrangement clearly increases the safety of train operation in a system of this type.

Although I have herein shown and described only one form of railway trafiic controlling apparatus embodying my invention. it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is;

1. In combination, a stretch of single track over which trafiic moves in both directions. signals governing the entrance of tralfic into said stretch, intermediate signals located at intervals along the stretch for governing traffic in both directions through the stretch. all

of said signals being capable of indicating these conditions will be obvistop, caution, and proceed, manually operable means for separately controlling the signals governing the entrance of tralfio into-said stretch, in either direction, and means for rendering said manually operable means ineffective to cause such entering signals to in- I dicate caution or proceed unless all of the opposing intermediate signals indicate stop.,,

- p In combination, a'stretch of single track over which traffic moves in both directions, a first signal for governing traffic in one direction through said'stretch, a first polarized line relay, means efiective Whensaid first line relay is deenergized for causing said first signal to indicate stop, manually operable means for causing said first signal to display a can tion indication when said first line relay is energized by currentiof one polarity and a proceed indication when said first line relay is energized by'current of theother polarity,

a second'signal for goi' erning tra ficin the opposite direction through said stretch, a second polarized line relay; means controlled by said second linerelay forfcontrolling said second signal in such manner that said second signal indicates stop, caution, or proceed ac cording as'said second line relay is 'deenergized or is energizedby current of one polar 'ity or the other; manually operable means for at times supplying said second line relay piedand said second line relay is deenergized. Y 3. In combination, a stretch of single track over which trafiic moves in both directions,

a first signal for go-verningtrafii'c in one di rection through said stretch, a firstpolarized line relay, means efiectivewhen said first line relay is deeiiergized for causing said first signal to indicate stop, manually operable nieans'for causing said first signal to display a caution indication when said first line relay is energized by current of one polarity and a proceed indication when said first line relay is energized by current of the other polarity, a second signal for governing traffio in the opposite direction through said stretch, a second polarized line relay; means controlledby said second line relay for controlling said second signal in such manner 7 that said second signal indicates stop, caution, or proceed according assaid second line relay is d eenergized or is energized by cur-, rent of one polarity 'orthe other, a slowreleasing repeaterrelay controlled by said second line relay, manually operable means for at' times supplying said second line relay with current of. one polarity or p the other when the portion-of said stretch between said signals is unoccupied, and'means for at times supplying said first line Y relay with current '8 Y i o 1,848,640

of one polarity or the other when the portion of said'stretch between said signals is unoccupied and saidrepeater relay is deenergized.

4. In combination, a stretch of single track overwhich trafiic moves in both directions, a first signal for governing traffic in one direction through said'st-retch, a first polarized line relay,"means efiectivewhen said first line relay is deenergized for causing said first signal to indicate stop, manually operable means for causing saidfirst signal to display a caution indication when said first line relay is energized by current of one polarity and a proceed indication when said first line relay is energized by current of the other polarity, a second signal located at some distance from said first signal for governing trafiic in the o 3 osite direction through said stretch 'a second polarized line relay; means controlled by said second line relay for controlling said second signal in such manner that said second signal indicates stop, caution, or pro-' ceed according as said second line relay is deenergized or is energized by current of one polarity orthe other; manually controller means for at times supplying saidsecond line relay with "current of oiiepolarity or the other when the portion of said'stretch between said signals is unoccupied, means for supplying said first'line relaywith current of one polarity when the portion of track betweensa'id signals is unoccupied and said second line relay is deener-gized; and means for supplying said first line relay with current of the other polarity when the portion of track between said signals is unoccupied, said second line relay is deenergi'zed, and the portion of'track immediately beyond said second'signal for traific moving in the opposite direction from that governed "by said second signal is occupied.

5, In combination, a stretch of single track over which trafic moves in both directions.

7 a first signal for governing trafiic in one direction through said stretch, a first polarized line relay, means effective when said first line relay isdeenergized for causing said first signal to indicate stop, manually operable means for causing said first signal to display a caution indication when said first line relay is energized by current of one'polarity and 1 a proceed indication when said fir t line relay is energized by current of'tlie other polarity, a second signal located at some distance from said first signal for governing traific in the op posite direction through said stretch, a second polarized line relay; means controlled by said second line relay for controlling said second signal in such manner that said secondsignal indicates stop,'caution, or'proc-eed according as said secondline'relay isdeenergized is energized by current of one polarity or the other manually operable means for at times supplying said second line relay with current of one polarity or the other when the portion of said stretch between said signals is unoccupied, and said first llne relay 1s deenerglzed, and means for at times supplymg sald n first line relay with current of one polarity or the other when the portion of said stretch between said signals is unoccupied and said second line relay is deenergized.

6. In combination, a stretch of single track over which trafiic moves in both directions, signals for governing traiiic in one direction through said stretch and other signals for governing traflic in the opposite direction through said stretch, a plurality of line relays one associated with each signal and each arranged to control the associated signal in such manner that the associated signal indicates stop when the relay is deenergized, and means for controlling said relay in such manner that a relay associated with a signal which controls traliic in one direction cannot become energized unless the relay associated with the opposing signal which governs the entrance of traffic into the same portion of the stretch is deenergized.

7. In combination, a stretch of single track over which trafiic moves in both directions, signals for governing traific in one direction through said stretch and other signals for governing trafiic in the other direction through said stretch, a plurality of line relays one associated with each signal and each arranged to control the associated signal in such manner that the associatedsignal indicates stop when the relay is deenergized, and means for energizing eachline relay when and only when the portion of track between the associated signal and the signal next in 7 advance governing traflic in the same direction is unoccupied and the line relay associated with the signal next in advance governing trafiic in the opposite direction is deenergized. 1

8. In combination, a stretch of single track over which traflic moves in both directions, head block signals governing the entrance of traffic into said stretch, intermediate signals located at intervals along the stretch for governing traflic in both directions through the stretch, a plurality of line relays one associated with each of said signals'and each arranged to control the associated signal in such manner that the associated signal indicates stop when the line relay is deenergized, and means for controlling said line relays in such manner that the line relay associated with each head block signal cannot become energized unless all of the line relays associated with the intermediatesignals which control traflic in the opposite direction are deenergized and all of the line relays associated with the intermediate signals which control traflic in the same direction are energized.

9. In combination, a stretch of single track over which traflic moves in both directions,

signals for governing traffic in one direction through said stretch and other signals for governing trafiic in the other direction through the stretch; a plurality of line relays one associated with each signal and each arranged to control the signal with which it is associated in such manner that the signal will indicate stop,caution,or proceed according as the associated relay is deenergized or is energized by current of one polarity or the other; means for at times supplying each line relay with current of one polarity when the portion of track between the signal controlled thereby and the signal next in advance governing traflic in the same direction is unoccupied, the line relay associated with the signal next in advance governing'traflic in the same direction is energized, and the line relay associated with the signal next in advance governing traiiic in the opposite direction is deenergized; and means for at other times supplying each line relay with current of the opposite polarity when the portion of track between the signal controlled thereby and the signal next in advance governing traf- -fic in the same direction is unoccupied, the

line relay associated with the signal next in advance governing trahic in the same direction is energized, and the line relay associated with the signal next in advance governing trafiic in the opposite direction is deenergized.

In testimony whereof I affix my signature.

JOHN E. MGCAULLEY.

DISCLAIMER 1,848,640.J0hn E. McO'aulley, San Francisco, Calif. RAILWAY TRAFFIC CONTROL- LING APPARATUS. Patent dated March 8, 1932. Disclaimer filed April 22, 1936, by the assignee, T he Union Switch (Q) Signal Company. Hereby disclaims the subject matter of claims 1, 2, 4, 5, 6, 7, 8, and 9.

[Ofiicial Gazette May 12, 1936.] 

